Process for saturating fabric



Aug. 1, 1933- J. ZAVERTNIK EI AL PROCESS FOR SATURATING FABRIC FiledSept. 11, 1929 2 Sheets-Sheet l FABRIC INVENTOR JUSEPH ZAVfAT/V/K & B YAltman/Ewan! ATTORNE/ Aug. 1, 1933- J. ZAVERTNIK El AL PROCESS FORSATURATING FABRIC Filed Sept. 11, 1929 2 Sheets-Sheet 2 Patented Aug. 1,1933 UNITED STATES PATENT OFFICE PROCESS FOR SATURATING FABRIC 1Application September 11, 1929 Serial No. 391,854

9 Claims. (Cl. 91-68) Our invention relates to a process for theimpregnation of porous fabrics such as paper, felt, strawboard, cloth,-and the like. It pertains more particularly to the production of roofingpaper,

artificial shingles, building-paper, and' similar materials, byimpregnation of porous fabrics with hot tar or asphalt, but it isgenerally applicable to the impregnation of porous fabrics with anysaturant in fluid condition.

10 In the production of roofing paper or artificial shingles, thecontinuous impregnation process is usually employed. A roll of felt orother suitable fabric is unwound by machinery and the moving felt ispassed through a bath of a fluid saturant,

after which it travels out of the bath and moves in the air for asufiicient time to permit the hot fluid saturant to harden. Squeezerolls may be employed to express the excess saturant and to give anydesired surface appearance to the prod- 750 not.

Our invention is particularly useful in the continuous type ofsaturation process described, although it is also applicable to a batchprocess, in which only one piece of fabric is treated at a time.

One of the advantages of our process is the more uniform impregnation ofa fabricwith a saturant. It also providesfor the effective use of adifferential pressure to promote the saturation of the fabric. Anotheradvantage of our process lies in the initial application of a liquid tothe fabric to make it more pliable and adaptable to the shape of themechanism with which it is to contact during impregnation. Otheradvantages will become apparent.

In describing our invention, reference will be made to the appendeddrawings in which Fig. 1 shows in cross-section an illustrativemechanism with which our process may beused, and Fig. 2

shows a fragmentary vertical section partly in elevation taken throughsubstantially the center of spokes E and H, the rolls B, P, R and Q andthe spray S being omitted for the sake of clearness.

In the drawings, (A) indicates a sheet of fabric undergoing treatment,and (B) is an idler roll, preferably heated, over which it passes. Afterpassing over the idler roll (B), the fabric (A).

r moves downwardly, as indicated by arrows, and

contacts with the revolving drum (C). The

drum (C) shown in the drawings has a perforated or foraminouscylindrical surface, the ends C of which may be closed by solid plates.

The perforated or foraminous surface of the drum (C) ispreferably ofsuch width that the fabric (A) will completely cover the perforations.

A stationary drum (D) is concentrically positioned within the drum ,(C)and is supported by means of the radial spokes E) (F), (G), (H), (I) and(J) from a hollow shaft (K) having a diameter smaller than the insidediameter of the sleeves 3 having flange 1 bolted as at 2 or otherwisesecured to the ends C of the drum (C). The ends of the hollow shaft (K)pass through the sleeves 3 and are journaled in demountable bearings 10,which may be removed from the pedestal or supports 11 so that theassembly may be readily taken apart. The ends of the shaft (K) areprovided with closure plates 8, one of which has an opening which may beconnected to a suction pump to create a suction in shaft (K).

The sleeves 3 are rotatably mounted on the hollow shaft (K), the portionof the shaft (K) concentric with the sleeve 3 having a bearing surface7. A gear 6 is keyed or otherwise secured in driving relation with thesleeve 3 and this gear is rotated from a suitable source of power (notshown) to rotate the drum (C).

The radial spokes (G), (H) and (I) are hollow and serve as connectingpassages between the space within the shaft (K) and the lower portion(L) of the annular space between the cylindrical surfaces of the drums(C) and (D). Plates (M) and (N) are fixed to the cylindrical surface ofthe stationary drum (D) and fit closely at their, outer edges againstthe inner surface of the drum (C). A pair of end plates M N extendcircumferentially about the lower portion of the cylindrical surface ofthe drum (D) and connect plate (M) with plate (N) near the sides of thedrum (D) as shown in Fig. 2. These end plates extend across the annularspace between the stationary and movable drums and, with the plates (M)and (N), form the boundaries of the annular space or chamber (L)connected by the hollow radial spokes to the shaft (K). These plates maybe positioned to make the chamber (L) of suitable volume and location.

The concentric drums (C) and (D) are positioned in a tank (0) which isfilled with a saturant to a point preferably above the plates (M) and(N). Suitable stufiing boxes 4 may be used where the sleeves 3 securedto the tank (C) pass through the ends of the tank (0) Also, a gland orstufling box 5 is provided where the hollow shaft (K) emerges from thesleeve 3. g

A partial vacuum may be maintained within the annular space (L) by asuction applied to the hollow shaft (K) and transmitted to this spacethrough the hollow radial spokes (G), (H)

' its opposite sides.

and (I). The fabric (A) after passing over the lower portion of thecylindrical surface of the perforated tank (C) may pass over an idlerroll (P) and squeeze rolls (Q) and (R) which act to squeeze out anyexcess saturant.

As the fabric (A) leaves the idler roll (B) its top (drum-side) surfaceis coated with a suitable liquid, which may be the same as the saturantin the tank (0), at a rate sufficient to effectively cover the surfaceof the fabric which later is to contact with the surface of the drum(C). This liquid may be applied by a spray from a pipe (S). An apron (T)extending downwardly to rest upon the drum (C) at a point below thecenter line, may be suspended from the pipe (S) to prevent the sprayedliquid from passing into the drum (C) before contacting with the fabric(A), or before passing the baffle (M).

The liquid sprayed upon the drum-side of the fabric renders the fabricpliable and will cause it to adjust closely to the surface of the drum(C). By adjusting the force of this spray, the penetration of the liquidinto the fabric may be regulated. The fabric thus coated travels at thesame speed as the periphery of the drum (C) and this liquid, by fillingany crevices and small apertures, forms a complete seal between thatportion of the perforated surface of the drum (C) which is opposite thespace (L), and the adjacent surface of the fabric (A).

As thefabric (A), coated upon its drum-side, passes through the saturantin the tank (0), the saturant is forced into and through the pores ofthe fabric by the difference in pressure upon The degree of penetrationmay be controlled by regulating this differential pressure or byregulating the speed of rotation of the drum (C).

Any excess of saturant upon the inner side of -the drum (C) may bewithdrawn through a pipe (U) and as shown diagrammatically in Fig. 1,may be returned to the tank (0) by a pump (V). In Fig. 2 the pipe U isshown passing through a stuffing box 9 in plate 8 to a suitable point ofdisposal. If desired, the liquid level-in the tank (0) may be keptconstant by adjusting the quantity of liquid added through thespraypipes (S), or thismay be accomplished by adding saturant directlyto the tank (0) Our invention has been described with reference to anapparatus in which a partial vacuum is maintained upon one side of thefabric (A). It is apparent that the differential pressure could beobtained by increasing the pressure upon the outside .of the fabricrather than by reducing that upon the inside. It is further apparentthat the apparatus described is merely illustrative of one. of manyforms of apparatus with which the process could be used.

The advantages of our invention thus described, are believed to beobvious. The fabric is made pliable by the application of a saturantbefore contacting with the drum (C). The sealing action of the saturantlessens the possibility of bypassing the saturant under the fabric tothe perforations in the surface of the drum (C). The resultant effectbeing an increase in the uniformity and speed of the penetration.

- Although in the specific application of our invention which has beenshown and described, the impregnation is accomplished by passing thefabric (A) through a tank of liquid, it is apparent that the saturantmay be applied by other means, such as a series of sprays. It is alsoapparent that the application of the liquidor saturant to the fabricbefore contacting with the rotating drum may be accomplished by othermeans, such as by dipping the fabric or by the use of a feed roll, andthat other than the saturating fluids may be used for rendering thefabric pliable.

When our invention is employed for the purpose of saturating fabric witha bituminous material, such as tar, asphalt, or pitch, the saturant mustbe used while hot, since it tends to solidify at normal temperatures. Insuch a case, the saturant may be readily maintained in*a fluid conditionby means of heat applied in any convenient manner to the pipe (S),-thetank (0) or to their contents. It should be noted, however, that ourinvention is equally applicable to the saturation of fabric at roomtemperature with substances that remain fluid at such 'temperatures.

Now having described our invention, we claim:

1. In a process for impregnating fabric in which said fabric issupported'on a perforated surface during impregnation with a saturantand a differential pressure is. applied to opposite sides of the fabricto promote impregnation, the step which comprises first applying a fluidto one side of the fabric to render it more pliable and adapted to fltclosely to said surface and thereafter passing the side of the fabric towhich fluid has been applied into contact with said perforated surface.

2. A process for impregnating fabric which comprises first applyingafluid to said fabric to render it more pliable, subsequently supportingsaid pliable fabric on a perforated surface, and applying a fluidsaturant to said fabric while maintaining a suction on the supportedside.

3. A process for impregnating fabric-which comprises applying fluidsaturant to one side of said fabric to render it more pliable, passingthe coated side of said fabric in contact with a perforated supportingsurface, and applying fluid saturant to said fabric while maintaining asuction on the supported side.

4. A process for impregnating fabric which comprises. spraying a fluidupon said fabric to render it more pliable, subsequently supporting saidpliable fabric on a perforated surface and applying a fluid saturant tothe exposed side of said fabric while maintaining a differentialpressure between the supported and exposed sides of said fabric.

5. A process for'impregnating fabric which comprises applying the liquidto one side of the fabric, subsequently supporting the side of saidfabric to which liquid has been applied upon a perforated surface,applying a saturant to the other side of said fabric and continuouslysubjecting the fabric to a differential pressure during the applicationof saturant to the side thereof opposite to that to which liquid isfirst applied.

6. In a process for impregnating fabric in which tne fabric is supportedon a perforated drum during impregnation with a saturant and adifferential pressure is applied to opposite sides of the fabric topromote impregnation, the improvement which comprises first applying afluid to one side of the fabric to render it more pliable and adapted tofit closely to said perforated drum, and thereafter passing the side ofthe fabric to which fluid has been applied into contact with saidperforated drum.

7. In a process for impregnating fabric in which the fabric is supportedon a perforated cylindrical surface during impregnation with a liquidsaturant and suction is applied to one side of the fabric to promoteimpregnation, the improvement which comprises first applying liquidsaturant to oneside of the fabric to render it more pliable and adaptedto fit closely to said cylindrical surface, and thereafter passing theside of the fabric to which the liquid saturant has been applied intocontact with said cylindrical surface.

8. In a continuous process for impregnating a moving Web of fabric inwhich the fabric is supported on a revolving perforated cylindricalsurface during impregnation with a saturant and a differential pressureis applied to opposite sides of the fabric to promote impregnation, theimprovement which comprises continuously applying a fluid to one side ofthe web of fabric to render it more pliable and adapted to fit closelyto said revolving cylindrical surface, and thereafter contacting theside of the fabric to which fluid has been applied with said revolvingcylindrical surface.

9. In a process for continuously saturating a moving web of felt inwhich said felt is supported on a revolving perforated drum duringsaturation with bituminous material and a suction is applied to one sideof the felt to aid the saturation, the improvement which comprises firstapplying bituminous liquid to one side of the felt to render it morepliable and adapted to fit closely to said revolving drum, andthereafter passing the side of the fabric to which the bituminousmaterial has been applied into contact with the revolving drum.

JOSEPH ZAVERTNIIK. ALEXANDER, A. MACCUBBIN.

